Wire coil binding machines



Sept. Z8, 1965 E. LoHR ETAL 3,208,484

WIRE COIL BINDING MACHINES Filed Dec. 19, 1962 2 Sheets-Sheet 1 Sept. 28, 1965 E. LoHR ETAL WIRE COIL BINDING MACHINES 2 Sheets-Sheet 2 Filed Dec. 19, 1962 United States Patent O 3,268,484 WIRE COIL BINDING MACHINES Ernst Lohr, Usinger Strasse 29, Cologne-Kalk, Germany,

and Paul Schmidt, Lustheider Strasse 34, Cologne- Vingst, Germany Filed Dec. 19, 1962, Ser. No. 245,793 Claims priority, application Germany, Dec. 23, 1961,

65,313 7 Claims. (Cl. Mtl-93.6)

The invention relates to a twisting device for a wire coil bending machine.

Machines are known for binding ring shaped wire coils in which a piece of binding wire is applied from below against a suspended or standing wire coil and bent up into U-form about the cross-section of the coil, the ends of the binding wire then being twisted by a twisting device brought against the inner periphery of the coil. During this operation, the cross-section 4of the coil is pressed together by the pressing device for the binding wire, by a pressing device acting on both sides of the coil crosssection and finally by the twisting operation. After the first binding, the wire coil, which is, for example suspended on a hook, can be lifted a little and turned through an angle corresponding to the number of bindings to be made, and lowered on to the hook whereupon the next binding operation can commence.

Such binding machines can be xed in position. They can however also be movable for a short distance below and parallel to a conveyor which carries suspended on hooks wire coils coming from a rolling or drawing mill, so that during the binding operation the binding machine can be moved together with the conveyor. After binding a coil, the binding machine is returned to its starting position. The entry of a coil of wire into the binding machine automatically starts movement of the machine with the conveyor and the initiation of the binding operations, while the return of the machine is caused by the completion of the last phase of the binding operations.

In these known wire coil binding machines, the twisting head of the twisting device is movable on a slide guided in the machine frame towards the periphery of the coil so that a slotted twisting plate in the twisting head can engage and twist the ends of the binding wire bent around the cross-section of the coil. Advantageously, though this is not essential because other arrangements can be used, the twisting head is brought into the wire coil so that the twisting head twists the ends of the binding wire on the inside of the cross-section of the coil. The twisting plate has radial slots by which it has to engage the ends to be twisted of the binding wire in order to be able to ei'lect the twisting operations. So that the ends of the binding wire bent into U-form about the cross-section of the coil can enter the slots in the twisting plate, the ends of the binding wire can be pressed against the rim of the twisting head by closing rams or bending members movable towards one another. These bending members or closing rams are carried by longitudinally movable rods which are guided in the machine frame on either side of the wire coil to be bound and can be moved by means of pneumatic or hydraulic working cylinders arranged in fixed position in the machine frame.

These twisting devices in the known binding machines have certain disadvantages. In particular, the bending members carried by the rods do not lead the ends of the binding wire into the slots in the twisting head with such certainty that a faulty binding can be avoided. 4Because the slidable twisting head and the two bending members are guided independently of one another in the machine frame, a common working position of these three elements lies at a relatively considerable distance from their slideways so that even small inaccuracies in the slideways which are unavoidable Von account of wear, hinder the exact cooperation of these elements. This is further made most objectionable because the wear of the slideways both in amount and in direction can be different so that the inaccuracies in the slideways add up at the working position. Through these errors faults in the cooperation of the three elements occur which can only be rectied by frequent and lengthy adjustment of the individual slideways. Further, movements of the bending members must be very accurately timed in relation to the movements of the twisting head, the twisting plate, and the devices which bend the binding wire into U-f-orm about the cross-section of the coil.

These disadvantages of the known twisting devices are mitigated according to the invention by the bending members for bending the ends ofthe binding wire being slidably guided in the twisting slide in the direction of movement lof the slide towards one another and against the twisting plate.

This arrangement of the bending members has they advantage that the bending members can now be functionally and constructionally associated with the twisting head and the twisting plate thereof into a unit, that is to say that all the elements of the twisting device are arranged on or in the twisting slide and the twisting head together with the bending members slide in guides which are rigidly connected with the bearings of the twistingA plate, that is with the twisting head, and reach right up to the twisting plate, with the parts cooperating in the working position being relatively correctly located so that eXact cooperation is made possible.

Advantageously, the bending member which is pressed against the outer half of the periphery of the twisting plate is secured to a frame straddling the twisting plate, which frame is guided in the twisting slide while the bending member movable against the inner half of the periphery of the twisting plate is secured to a slide block guided on the twisting slide inside said frame.

When the twisting slide is moved forward, the bending member secured to the frame can be moved into its outermost position while the bending member secured to the slide block is moved to the opposite innermost position so that ample room is available for bending the binding wire into U-form about the cross-section of the wire coil. Both bending members are thereafter moved against the twisting plate so that the ends of the binding wire are reliably entered into the slots in the twisting late.

p In the known binding machines it happens that the turns of a coil do not all lie uniformly within an annulus but some turns project irregularly into the central space of the coil. If now the two closing rams or bending members are to press the ends of the binding wire into slots in the twisting plate, any turns projecting into the interior of the coil hinder the entry of the binding wire ends and thus the carrying out of the binding. This disadvantage also is mitigated by the device according to the invention. When the whole twisting device slides into the working position, the bending member secured to the frame and located at the front end of the device is carried forward pushing aside any impediments which may be within the coil. Advantageously, the front surface of this bending member is therefore made of drop or wedge form. The binding wire ends can be brought unhindered through the frame opening into their correct position into the slots of the twisting head.

In further development of the invention recesses are provided in the sides of the bending members facing the twisting plate of such form that in the closed position the bending members also partially overlap the upper and lower surfaces of the twisting plate. These bending members not only guide the binding wire ends into the slots in the twisting plate but also press the wire ends up to the inner ends of the slots. The ends of the binding wire can also be held in this position during the twisting operation. This formation of the bending members makes it possible to influence the tension under which the ends of the binding wires are twisted.

Yet another development of the invention consists in the provision of cutting edges on the upper inner edges of the bending members which cooperate with cutting edges on the under outer edges of the twisting head. When the bending members are moved towards one another these cutting edges cut olf the projecting ends of the binding wire to be twisted so that in spite of variations in the cross-section of the wire coil to be bound the ends of the binding wire to be twisted are always of the same length.

Further features of the invention will appear from the following description in which an example of embodiment of a twisting device according to the invention is described in detail with reference to the accompanying drawings.

FIGURE 1 is a view in longitudinal section and partly in elevation of the twisting device according to the invention in its working position with the bending members brought up to the twisting plate,

FIGURE 2 is a side view of the twisting device,

FIGURE 3 is a plan view of the twisting device, and

FIGURE 4 is a detail view on a larger scale of the twisting plate, the bending members and cutting edges.

FIGURES 1 to 3 show a twisting head 1 and twisting plate 2 together with a drive for the twisting plate 2 comprising a driving motor 3, coupling 4, gear box 5, transmission shaft 6 and worm gear 7 which are carried by a slide 8 which is longitudinally slidable on a slideway in machine frame 9. This slide 8 is moved forward into the twisting position and retracted into the starting position by a working cylinder 10 preferably pneumatic, piston rod 11 of which is pivoted to a lug 12 fixed to the slide 8. The working cylinder 10 is mounted by spherical seatings 14 in a housing 13 fixed to the machine frame 9. At about the height of the twisting plate 2, according to the invention, two oppositely movable bending members 15 and 16 i.e. movable against the twisting head 1 are mounted on the slide 8 slidable in the direction of movement of the slide 8. When the slide 8 is moved forward, these bending members 15 and 16 together with the twisting head 1 are brought into the working position.

The bending member 15 which is movable against the outer half of the periphery of the twisting plate 2 is held by a frame 17 which straddles the twisting plate 2 and is guided on the slide 8. FIGURES 2 and 3 show piston rods 18 and 18 pivoted to either side of this frame 17, and working cylinders 19 and 19 thereof are mounted by spherical seatings in a housing 20 secured to the slide 8.

The bending member 16 movable against the inner half of the periphery of the twisting plate 2 is held by a slide block 21 slidable within the frame 17 on the slide 8. To this slide block 21 is pivoted a piston rod 22 working cylinder 23 for which is mounted by spherical seating rings 24 also in the housing 20, between the two working cylinders `19 and 19. The bending members 16 is exchangeably secured to the slide block 21 by a cotter pin 25.

The cylinders 19, 19 and 23 for'effecting the movements of the bending members 15 and 16 are arranged at the same level and parallel to one another as well as parallel to the cylinder 10 for movement of the slide which is arranged in the longitudinal midplane of the twisting device beneath the cylinder 23.

FIGURES 1 and 4 show recesses 26, 26 provided in the sides of the bending members 15, 16 which face the twisting plate 2 being of such form that the two bending members 15, 16 can almost completely overlap the twisting plate. By this means it is possible for the bending members 15 and 16 to press the ends of binding wire 29 against shaft 30 of the twisting plate 2 during the twisting operation with an adjustable pressure so that the wire ends can be twisted under an adjustable tension.

On the upper inner edges of the bending members y15 and 16 cutting blades 31 and 32 are provided which cooperate with cutting blades 33 and 34 which are positioned into the lower outer edges of the twisting head 1. When the bending members 15 and 16 are moved towards the twisting plate, the cutting blades 31 to 34 cut off excess length 35 of the binding wire 29 which varies according to the cross-section of the coil to be bound. The pieces of binding wire supplied to the machine are suited to the normal cross-section of the coils to be bound but this cross-section may vary from coil to coil and the length of the binding wires cannot be made exactly correct for the cross-section of every coil so that various lengths of wire end to be twisted will present themselves. By this cutting off arrangement 31 to 34, twisted wire ends 36 will always be of the same length even though the cross-section of the coils may vary. FIGURE 4 on the righthand side shows such an end 3S being cut oit and it also shows the same wire end after the bending member has brought it against the shaft 30 and the shaft has rotated through half a revolution.

The twisting device is so controlled by means of limit switches, stops or other corresponding means that together with the known initiation of the forward movement of the slide 8, first the bending members 15 and 16 are moved apart, then these members move towards one another and against the twisting plate 2 to cut off and bend in the ends of the U-formed binding wire 29 laid around the cross-section of the coil. The driving motor 3 for the twisting plate 2 is started when the bending members 15 reach their closed position, and this motor is automatically inactivated after the predetermined number of revolutions and the slide 8 is then returned to its starting position. As shown in FIGURES 2 and 3, a shaft 41 which carries a cam disc 42 is driven from the gear box 5 through an auxiliary gear 40. This cam disc 42 acts upon Ia lever 43 of a switch 44 which inlactivates the driving motor 3 after a predetermined number of revolutions `and initiates the return of the slide 8.

The inactivation of the motor 3 is so controlled or set that the radial slots in the twisting plate 2 come to rest when they extend in the direction of the movement of the slide and thus perpendicular to the plane of the wire coil to be bound so that the ends of the binding wire can be correctly brought into -slots in the twisting plate 2 by the bending members 15 and 16. The twisting plate 2 is therefore braked by the motor 3 serving as a magnetic brake at the instant when the slots in the twisting plate align with the longitudinal midplane of the twisting device. To achieve as high `as possible a speed in the forward and backward movement of the slide 8 and of the bending members 15 and 16, the pistons in the working cylinders 10, 19, 19 and 23 are actuated by compressed air. In order to avoid violent contact of the pistons in their end positions, pneumatic damping devices are provided in the working cylinders which make possible a smooth run out of the pistons at their end positions. Thus, each piston may have on its end face a conical pin, which at the rear end position of the piston sealingly enters a bore at the rear end of the working cylinder and thus forms an air cushion between the body of the piston and the wall of the cylinder which resilient- 1y resists the piston and escapes through damping nozzles. Correspndingly, a cylindrical enlargement is formed on the piston rod in the neighborhood of the piston which before the forward end position of the piston is reached, sealingly enters a bore and thus forms a resilient and damping air cushion between the annular end surface of the piston and the cylinder walls.

The invention is not to be confined to any strict conformity to the showings in the drawings, but changes or modifications may be made therein so long as such changes or modifications mark no material departure from the spirit and scope of the appended claims.

What we claim is:

1. In a twisting device for a wire coil binding machine having a machine frame, a slide movable longitudinally on the frame to and from a twisting position, a twisting head and a twisting plate ca-rried by said slide with said twisting plate being provided with radial slots and being journalled in said twisting head, and a pressing means serving to bring the ends of a binding wire bent in U- form about the cross-section of the wire coil into the zone of the twisting plate, said pressing means including two oppositely movable bending members slidably guided in said slide in the direction of movement of the slide towards one another and against said twisting plate.

2. The twisting device as claimed in claim 1 including a pneumatic cylinder and piston assembly mounted on the machine frame with the piston rod thereof being connected to said :slide for moving the slide to and from the twisting position, a housing ixedly secured to said slide, a pneumatic cylinder and piston assembly mounted in said housing in parallel relationship operably coupled to said pressing means for moving said bending members toward and away from each other.

3. The twisting device as claimed in claim 1 including a motor, a drive connection between the motor and the twisting plate, switch means for inactivating said motor after a predetermined number of revolutions, a shaft driven by said drive connection .and cam means on such shaft for activating said switch means.

4. In a twisting device for a wire coil binding machine having a machine frame, a slide movable longitudinally on the frame to and from a position, a twisting head and a twisting plate carried by said slide wtih said twisting plate being provided with radial slots and being journalled in said twisting head, and a pressing means serving to bring the ends of a binding wire bent in U-form about the cross-section of the wire coil into the zone of the twisting plate, said pressing means including two oppositely movable bending members, a fr-ame straddling said twisting 6 plate and guided in said slide to which one of said bending members is attached, and a block slidably guided 0n said slide with-in said last-named frame to which the other bending member is secured whereby the bending members are guided slidably in said slide in the direction of movement of the slide towards one another and against said twisting plate.

5. The twisting device as claimed in claim 4 including a pneumatic cylinder and piston .assembly mounted on the machine frame with the piston rod thereof being pivotally connected to said slide for moving the slide to and from the twisting position, a housing iixedly secured to :said slide above and in parallel relationship to said cylinder and piston asesmbly, .a second cylinder and piston assembly mounted in said housing and being alrranged in the longitudinal center plane of said slide with the piston rod being connected to said block and a further cylinder and piston assembly mounted in said housing on each side of said second cylinder and piston assembly with the piston rods thereof being pivotally connected to the frame straddling the twisting plate whereby said second and further cylinder and piston assemblies move said bending members toward and away from each other.

6. The twisting device as claimed in claim 4 in which the sides of the bending members facing said twisting plate are provided with recesses of such configuration as to partly overlap the upper and lower surfaces of said twisting plate when said bending `members are moved toward each other.

7. The twisting device as claimed in -claim 4 in which said twisting head includes a lower edge, cutting surfaces carried by said lower edge, each of said bending members having an upper edge, and a cutting surface for each of such upper edges cooperable with the cutting surfaces of said twisting head for severing the projecting ends of the inner binding wire.

References Cited by the Examiner UNITED STATES PATENTS 690,037 12/01 Schuster 10G-3l CHARLES W. LANHAM, Primary Examiner. MARCUS U. LYONS, Examiner. 

1. IN A TWISTING DEVICE FOR A WIRE COIL BINDING MACHINE HAVING A MACHINE FRAME, A SLIDE MOVABLE LONGITUDINALLY ON THE FRAME TO AND FROM A TWISTING POSITION, A TWISTING HEAD AND A TWISTING PLATE CARRIED BY SAID SLIDE WITH SAID TWISTING PLATE BEING PROVIDED WITH RADIAL SLOTS AND BEING JOURNALLED IN SAID TWISTING HEAD, AND A PRESSING MEANS SERVING TO BRING THE ENDS OF A BINDING WIRE BENT IN UFORM ABOUT THE CROSS-SECTION OF THE WIRE COIL INTO THE ZONE OF THE TWISTING PLATE, SAID PRESSING MEANS INCLUDING TWO OPPOSITELY MOVABLE BENDING MEMBERS SLIDABLY GUIDED IN SAID SLIDE IN THE DIRECTION OF MOVEMENT OF THE SLIDE TOWARDS ONE ANOTHER AND AGAINST SAID TWISTING PLATE. 